RJ11 (6P2C) carries a single analog telephone line with the center pair (pins 3-4) for telephone handsets and DSL modem connections.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | Unused | Not connected | I/O |
| 2 | Unused | Not connected | I/O |
| 3 | Tip | Phone line tip positive | BUS |
| 4 | Ring | Phone line ring negative | BUS |
| 5 | Unused | Not connected | I/O |
| 6 | Unused | Not connected | I/O |